[Cryptography] 回复： Re: Question about Bitcoin's security model

[qbtc.core]

Hi Jon and Roland,

I completely agree with Jon's assessment regarding the double-edged sword of code immutability. The current culture of "ossification" in Bitcoin Core development goes beyond just living with legacy bugs—it presents an existential systemic threat when we consider cryptographic deprecation.

While the XZ Utils backdoor highlights human negligence, the impending threat of Quantum Computing (specifically Shor's algorithm breaking ECDSA) highlights systemic paralysis. Transitioning to NIST-standardized Post-Quantum Cryptography (like ML-DSA) natively on Layer 1 is becoming gridlocked: soft-fork workarounds would catastrophically destroy network throughput due to signature bloat, while structural hard forks are politically a non-starter.

In my recent independent tests integrating ML-DSA-65 into a Nakamoto-consensus environment, the sheer size of post-quantum signatures (several KBs) requires fundamentally re-architecting the underlying P2P network layer (e.g., expanding default TCP transport buffers, P2P message serialization limits, and block weight thresholds).

Regarding Roland's point on illegal media insertion: ironically, as we are forced to expand block capacity to accommodate these massive PQC signatures, the attack surface for embedding illegal data (like CSAM) via arbitrary data fields (e.g., OP_RETURN or Witness discount abuse) expands significantly. The community needs to enforce strict structural decoupling of functional cryptographic proofs from arbitrary data storage via rigid consensus rules, otherwise, the legal liability for node operators will only worsen.

Immutability is a brilliant feature until the underlying mathematics expire. After that, it becomes a tomb.

— J.
2026年7月24日 星期五 上午 3:59，Roland Ionas Bialke <webmaster at pro-wrestling.biz> 来信：

> Jon Callas schrieb am 22.07.2026 19:41 (GMT +02:00):
>
>>> On Jul 21, 2026, at 15:49, Roland Ionas Bialke <webmaster at pro-wrestling.biz> wrote:
>>>
>>> - There is also the possibility to insert illegal media content into the transaction history - like "cheese pizza". In the past there was rumours about it, but no proof. When illegal media content would be in the transaction history, everyone who is loading it down would be in the posession of illegal media content.
>>
>> This has already happened. I might be misremembering, but as I remember someone put a piece of CSAM into the bitcoin blockchain; NCMEC has removed it from their corpus, as I remember.
>>
>> I am not sure. And I am not sure, if there is a copyright on the headline from the article of the first Bitcoin block.
>>
>>> - One related problem is the centralization of the Bitcoin developing mailing list moderation! They can hide things and they can make up things.
>>
>> Me, I think that the major problem with many of these systems, especially bitcoin is immutability of the code. If you can't fix bugs, then you have to live with the bugs.
>>
>> Jon
>>
>> Indeed. And I think that the Jia Tan case (XZ Utils backdoor) showed that the most commited and best educated people - mass of people - become negligent with the time.
>>
>> -------
>>
>> I think there are additional dangerous things - maybe not for the network, but for users.
>>
>> One thing is, (in some countrys) you file a government tax report for your BTC and often after a certain time there is no tax to pay. But in therory every third party (or a governement body) could set of a fork and airdrop you alternative BTC's. And when the third party is setting up additional a manipulated oracle or a few manipulated markets, the alternative BTC is priced really high for a certain time. In my country it is called "income" and you have to pay tax for it or loose allowance. But I am an amateure in this topic.
>>
>> Another danger is a mining underage person. In my country (Germany) it is not allowed to profit of the work of a person below a certain age, and it is not allowed to make business with a person below a certain age. I think it is a good example for the other topic here on the mailing list. So it is possible, that you trade with a minor or there is a mining minor - and the BTC's becoming "tainted".
>>
>> Another thread to the Bitcon network are shutdowns of the internet. I think one solution could be to promote mesh netwoorks and create Bitcoin software for these mesh networks. A few month ago here on the mailing list I read a topic on analogue blockchains(?). And I think this would be interesting also - for the cases of internet shutdowns. Iran and Russia are the last and known cases for internet shutdowns.
>
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